Terminal for electrical apparatus



lJune 29, 1954 H. v. ELLIOTT TERMINAL FOR EECTRICAL APPARATUS W74/NVENTOR "IA NA .ATTORNEYS l Patented June 29, 1954 2,682,570 v TERMINALEon ELECTRICAL APPARATUSl Harold V. Elliott, Anderson, Ind., assignor toGeneral Motors Corporation, Detroit, Mich., a corporation of DelawareApplication October 26, 1949, Serial No. 123,687

2 Claims. (Cl. 174--153) This invention'relates to terminals for anelectrical apparatus, for example, ignition timers.

An object of the invention is to provide a terminal and means forinsulatingly supporting the terminal by a metal housing of the apparatussuch as the housing of an ignition timer having means for securing theterminal to the housing and to conductors within the housing, said meansbeing independent of the use oi any other device, such as a screw forfastening an external wire to the terminal. In the disclosed embodiment,this object is accomplished by the use of a termi-- nal comprising ascrew and a tubular nut threadedly engaged by the screw. The screw andnut extend within two non-conducting members, one of which extends fromthe interior through the housing and has a spline connection with thehousing and with the external non-conducting member. The tightening ofthe nut on the screw secures conductors within the housing to the head iof the screw and causes the non-conducting members to clamp the housingbetween them. The nut can be turned to permit loosening of the screwsuiciently to provide for removal or application of the conductorswithin the housing to n the head of the screw while the non-conductingmembers remain in loose assembly with each other and with the housing.The nut provides for the reception of a screw for the attachment of anexternal conductor to the terminal of which the nut forms a part.

Further objects and advantages of the present invention will be apparentfrom the following description, reference `being had to the accompanyingdrawing, wherein a preferred embodiment of the present invention isclearly shown.

In the drawing:

Fig. 1 is a plan view of an ignition timer having' a terminal embodyingthe invention.

Fig. 2 includes as a group of parts the terminal in section, a wireattached to a terminal clip, a lock washer and a screw used to attachthe lock Washer and the terminal clip to the tubular nut of the timerterminal.

Figs. 3 and 4 are end views of the terminal insulating members, theseviews being taken, respectively, in the direction of arrows 3 and 4 ofFig. 2.

Referring to Figs. 1 and 2, a housing It supports a breaker plate I Iattached to the housing by screws I2. Plate II supports a bracket I3which carries a stationary contact i A engageable with a movable contactI5 carried by circuit breaker lever I 6 journaled on a pivot post I'Iand insulated therefrom, said post being attached to l supported by theplate II.

. by slot 23 of bracket I3. This adjustment varies 2 the plate I I andproviding a pivot for the bracket I3 which is adjustable by the turningof a slotted disc I8 attached to an eccentric shank I9 pivotally Disc i2is received the location of a rubbing block 2l attached to lever I5relative to the ignition timer cam 22 against which the block is urgedby leaf spring 27 passing through a slot 28 in bracket I3 and' threadedinto plate I l, secures the bracket in adjusted position.

The terminal 24 (Fig. l) comprises, as shown` in Fig. 2, a screw 3D anda tubular nut 3| threadedly engaged by the screw. These terminal membersextend through non-conducting bodies 32 and 33. Body 32 has a splineconnection with the screw 30. For this purpose, body 32 has a squareopening 34 for receiving the square portion 36 of the shank of screw 30.Body 32 has a tubular extension 38 extending through a'hole 33 providedby the housing Ill which includes a notch 4I for receiving a boss I3 ofbody 32, thus providing a spline which is received by a groove 35 in theexternal insulating body 33 which provides a pocket 3l for receiving thetubular extension 38 of body 32. Thus body 32 is splinedh7 connectedwith housing I3 and with body 33. Body 33 provides a hole 42 forreceiving the nut 3I and provides a pocket 43 for receiving a lockwasher 44 and the head `of the screw 3l which is provided with crossslots (one shown at 45, Fig. 2) for receiving a screwdriver blade.

The screw 30 and the body 32 are assembled loosely together and areplaced within the hous- 4ing and are assembled therewith by movement ofthe tubular extension 38 through the hole 35 cf the housing, the rib 40being received by the notch 4I provided by the housing. The body 33 isassembled with the internal body 32 loosely, the groove 35 receiving therib 42. The lock washer 43 is assembled upon the nut 3| and, whilemanually holding parts 3G, 32 and 33 in assembly, the nut 3|V is screwedonto the threaded shank of the screw 30. Before the nut is tightened,the leaf spring 23 and a terminal clip 25a of Wire 25 are assembledbetween the head of the screw 30 and the body 32, said parts 23 and 25cthaving square notches for receiving the square shank portion 36 of thescrew 30. Then by use of a screwdriver, the nut 3| is tightened in orderto maintain the assembly as shown in Fig. 2, left. When the terminalmemy bers 30 and 3| are tightened together, the terminal assembly cannotturn relative to the housing Hl since body 32 is splinedly connectedwith housing It' and with body 33 and bodies 32 and 33 are provided,respectively, with cylindrical surfaces 32a and 33a which conform to theinterior and exterior surfaces of the housing I0.

`An external conductor, such as terminal clip:

5I) attached to a wire 5 I, is attached. to the termi nal nut 3| by ascrew 52 passing through a lock Washer 53, the screw 52 threadedlyengagingnut` 3|. The tightening or loosening ofthe screw' 52 does noteffect any turning of nut 3| by reason of the fact that its threads arefrictionally. held,v

by the threads 0f screw 3|! which is prevented from turning since itssquare shank portion 3B1is received by the square hole 34 in body 32which has a splined connection with housing I0. Nut 3|- cannot be turnedby threading the screw 52 therein also by virtue 4ci the fact that thehead of nut 3| is gripped by a lock washer which grips body trwhich issplinedly connected with body 32 which is splint-:diy connected withhousing I0;

While the embodiment of the present invention as herein disclosed,constitutes a preferred form, it is to be understood that other formsmight be adopted.

What is claimed is as follows:

l. In combination with an apertured wall of a metal housing, aninsulatedI terminal member adapted to pass through said aperture andcomprising a telescopic element including two insulated parts, the firstof said parts being adapted for insertion through said housing` apertureand comprising a shouldered member having a hole therethrough and areduced diameter extension thereon of sufficient length to extendoutwardly at the opposite side of said wall, the second of saidinsulated parts including a recess adapted to t over said outwardlyextending reduced diameter extension, said second part having a holetherethrough in substantial register with the hole in the rst part,means for holding said parts together in telescopic arrangement with theWall interposed therebetween, said means comprisingzayconductor'including maleI and female parts engageable withinsaidterminal member and accessible from either end of said member.

2. An insulating` bushing adapted to pass through an aperture in aconducting wall oomprisingi in;` combination, two nonuconductingmembers;v one of which is partially insertable through-said aperture soas to extend outwardly oisaid, wall` andthe other of which is adapted toembrace the outwardly extending portion of theliirst"` member at theother side of the wall, key means disposed between the embraced portionsof said members and engaging. the wall fcrpreventingrelative rotation ofthe members with respect4 to eachother and to the Wall. and means forpreventing axial displacementoff said members.,4 said meansy comprising.a conductor adaptedito draw said members into tight engagementywith-said wall, ,said conductor consisting of maleandfemale,membersaccessible from either end of saidbushing andrpassingthrough aligned holes extending axially withinsaid two bushing members.

References Citedin` the ille of this patent` UNITED `S'lIA'IES PATENTSNumber Name Date 1 1346,525 B'eetem July 13; 1.920 1,813,716 ThordarsonJuly 7; 1931 15931456 Gaston Oct. 31', 1933 2,304,334 Boucher et` alDec; 8, 1942 21.448,76@ Burke` Sept 7,1948 21,456,246 Berg etal.' Dec.14;,1948

